Sound-box for talking-machines.



' E. R. JOHNSON. SOUND BOX FOR TALKING MACHINES.

- APPLICATION FILED APR. 22,1902.

INVENTOR A TTORNEV ELDRIDGE R. JoHNsoN, or PHILADELPHIA, rnnnsrnnanra, nssrenoa no vreronf TALKING MACHINE oonranr, a conronarron on NEW JERSEY.

SOUND-3G3 FOR TALKING-MACHINES.

Specification of letters Patent.

Application filed April 22, 1902. Serial No. 104,162.

Patented Oct. 22, 1912.

To all whom it may concern: Be it known that I, Ernamcn R. JOHNSON,

acit-izen of the UnitedStat-es, and a resident of the city of Philadelphia, State of Pennsylvania, have invented certain new and useful Improvements in Sound-Boxes for TalkingsMa chines, of which the following is a full, clear, andexact description, re erence being had to the accompanying draw1ngs,'-form1ng part of this speclfication.

The main objects of this'invention are to' provide in a sound box an improved mounting for a diaphragm improved means of thereon is a longitudinal section of a sound box embodying my invention.

Referring to the drawlng, one embodimentof,this invention comprises a casing consisting of two sections, an annular front section 1, adapted to carry a stylus bar and a diaphragm, and rear section 2 adapted to be attached to a horn or sound amplifying or sound conducting device. These two sections may be secured together in any suitable manner, as for instance, by having the rear section telescope snugly withln the rear end of the front section, and held in means of a set screw 3.

To form a suitable support for a diaphragm, the inner surface of the front section 1 of the casing is provided with a conical or tapering surface forming an an nular seat 5, which preferably tapers in a direction away from the rear section 2 of the casing. It is not essential, however, that this seat should taper, although the tapering form facilitates the assembling of the parts of the sound box, and is otherwise advantageous, as will appear hereinafter.

' Secured to the seat 5, by means of a suitable cement, is an elastic ring or pad 6, which conforms to. the contour of the seat. In the instance illustrated this ring is pracposition by tically uniform in thickness and'conical in shape. Surrounded and supported by the.

ring 6 is a diaphragm 7 of the usual or my suitable construction. A small quantity of elastic cement such as rubber or any other suitable elastic cement, is applied to the periphery of the diaphragm, and adlwres to the inner surface of the pad or ring holding the diaphragm in position in the ring (I. If preferred, the ring 6 might be omitted and the circumferential surface of the din phragm secured by the yielding cement directly to the seat 5 of the casing.

A stylus bar 8 is yielding-1y connected to the front sectionl of the casing, and is connected to the diaphragm by means of 1 wire 9, one end of which is secured to the diaphragm and the other end of which projects through an aperture 10 provided therefor 'in the .inner end of the stylus bar, and is held in place by a set screw ll,"il1readed longitudinally through the inner end of the .stylus bar and engaging the wire.

One of the advantages of this construction is, that by loosening the set screw 11, the wire 9 may be withdrawn from the stylus bar and the, diaphragm may be removed from its seat without breaking the wire or destroying its connection with the dia phragm. This manner of connecting the diaphragm to the stylus bar also permits the diaphragm to be cemented in the casing in any convenient position without careful.

consideration of its distance from the inner end of the stylus bar, and then the wire 9 may be readily secured to the stylus bar without bringing upon the diaphragm; of this construction is that by having the seat 5 upon which the diaphragm is mount-ed, tapering as described, not only may the diaphragm and its annular ring be conveniently positioned in the casing but Another advantage also more or less space may be allowed, if

desired, between the ring and the casing and between the circumferential surface of the diaphragm and the ring for the yielding cement, by simply varying the positions of the ring and diaphragm, or the diaphragm might be secured by the cement directly to the tapering seat of the casing if preferred, without making any change other than to omit the ring and to readjust the diaphragm and its connection to the casing and stylus bar accordingly. A further advantage of this construction is that as the diaphragm is held in position only by the elastic cement in contact with the circumferential surface of the diaphragm, the plane surfaces or opposite sides of the diaphragm are free from contact with any part of the sound box casing or mounting of the diaphragm. The diaphragm is thus free to flex and vibrate through its entire area, and will respond faithfully to the most minute vibrations-of the stylus bar .or to the slightest sound any undesirable tensionvibrations of the atmosphere, and excellent 8. In a sound'box for talking machines, a results in sound recording and reproducing diaphragm having a narrow, circumferenmay therefore be attained. 7

Although only a single form has been illustrated in whichthis invention mav be embodied, the invention is not limited to the specific form shown, but obviously may be embodied in various forms without departing from the spirit of, the invention or the scope of the appended claims.

Havingthus described my invention what I claim and desire to secure by Letters Patent, is

1. In a sound box, the combination with a support, of a diaphragm located; therein, and an inclined bearing surface for the periphery of said diaphragm. F

2. In a sound box, the combination With a support, of a diaphragm located therein, an inclined bearing surface on theinterior of the support, an elastic covering for said inclined bearing surface against which the circumferential surface of the diaphragm rests andan elastic cement connecting said circumferential surface and said' bearing surface.

3. In a sound box, the combination with a casing, of a ring in said casing and having a tapering internal surface, and a diaphragm having its circumferential surface resting adjacent the tapering internal sinface of said ring and cemented thereto.

4. In a sound box, the combination with a casing of a diaphragm, an inclined seat supported in the casing adjacent which the peripheral edge of the diaphragm rests, a stylus bar mounted on the casing, and an adjustable connection between said stylus bar and said diaphragm whereby said dia phragm may be properly adjusted on its seat. p l

5. The combination with a sound box casing, of a diaphragm located therein, cement holding said diaphragm in position, a stylus bar yieldinglymounted on said casing, a pin rigidly secured to the diaphragm, said stylus bar being provided with an aperture through which said pin passes, and a set screw for holding the pin in position with respect to the bar.

6. In a soundbox, the combination with a casing of a diaphragm, and a ring having an interior conical surface, said diaphragm being supported within said ring and having substantially the entire surface of its side faces free from contact.

7. In a sound box, the combination with a casing, of a diaphragm, and a ring having an interior conical surface, the Quid. diaphragm having substantially the entire surfaces of its side faces free from contact with said ring, and means supporting said diaphragm at its periphery within said ring.

tial surface, and means having an interior" conical surface contacting only with said circumferential surface of said diaphragm for supporting the same within said sound box.

9. In a sound box for talking machines, the combination of 'a support for a diaphragm, a diaphragm having a narrow, circumferential surface, and means having an interior conical surface attached to'said support and to said diaphragm bysaid circumferential surface only for holding the latter in position.

10. In a sound box for talking machines, the combination with a support having an interior conical surface, of a diaphragm located therein, and cement upon the circum ferential surface only of said diaphragm, the plane surfaces of said diaphragm being substantially entirely free from the cement.

11. In a sound box for talking machines, the combination with a support having an interior conical surface, of a diaphragm located therein and elastic cement connecting said support with the circumferential curved surface only of said diaphragm, the plane surfaces being substantially entirely free from the cement.

12. In a sound box, the combination of a support having an inclined bearing surface, a diaphragm located within the same and having the circumferential surface of its.

edge adjacent said inclined surface, and elastic cement between said surfaces for holding said diaphragm in place.

13. The combination with a diaphragm, of conical means contacting substantially only with the peripheral edge of said dia-' phragm for holding said diaphragm in position.

14. In a sound box, the combination with a casing, of a diaphragm, a stylus bar connected to said diaphragm and yieldingly connected to said casing, said casing being provided with an internal annular surface surrounding and supporting said diaphragm and tapering toward said stylus bar.

15. In a sound box, the combination with a casing, of a diaphragm, a stylus bar yieldingly connected to said casing, and an adjustable connection between said diaphragm and said stylus bar, said casing being provided with an internal annular surface surrounding and supporting said diaphragm and tapering toward said stylus bar.

In witness whereof I have hereunto set my hand this 15th day of April, A. D.,1902.

ELDRIDGE It. JOHNSON. Witnesses:

E. H. IViLLAaD, JAS. G. STIKELEATHER. 

